I believe the chinese vendors deliberately mislead buyers on the price. I have looked into a number of supplements and they may say, for example, $100 a kilo for something that costs here $5 a gram so naturally that generates a lot of interest. When you write them asking about buying they may say 1200 a kilo, which is not bad but far higher, obviously. I ask them how much I would have to buy to get the 100 price and they say that price was a "mistake" and they will fix it. But you check the ad a month later and its the same. I see this not in one or two vendor ads but in many but not all across the board, its very common no matter what you are looking for. I think its deliberate deception, a come-on price to get you in the door then hit you with the real price.
I've also had them, I believe, call customs and tell them exactly what it was they sent when it was something subject to regulations. They will label it as something else but my vendor told me he called customs about it. I asked why and got an evasive answer but the letter I got when they confiscated it said the exact name of the substance which they could not have detected without sophisticated lab work. Beware! its not just the quality to watch out for.